/// <summary>
/// Raises the <see cref="E:BeforeSearching"/> event.
/// </summary>
/// <param name="e">The <see cref="BeforeSearchingEventArgs"/> instance containing the event data.</param>
protected virtual void OnBeforeSearching(BeforeSearchingEventArgs e)
{
if (this.BeforeSearching != null)
{
this.BeforeSearching(this, e);
}
}
/// <summary>
/// Handle the SearchForVirtualList event, which is called when the user types into a virtual list
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected virtual void HandleSearchForVirtualItem(object sender, SearchForVirtualItemEventArgs e)
{
// The event has e.IsPrefixSearch, but as far as I can tell, this is always false (maybe that's different under Vista)
// So we ignore IsPrefixSearch and IsTextSearch and always to a case insensitve prefix match.
// We can't do anything if we don't have a data source
if (DataSource == null)
{
return;
}
// Where should we start searching? If the last row is focused, the SearchForVirtualItemEvent starts searching
// from the next row, which is actually an invalidate index -- so we make sure we never go past the last object.
int start = Math.Min(e.StartIndex, DataSource.GetObjectCount() - 1);
// Give the world a chance to fiddle with or completely avoid the searching process
var args = new BeforeSearchingEventArgs(e.Text, start);
OnBeforeSearching(args);
if (args.Canceled)
{
return;
}
// Do the search
int i = FindMatchingRow(args.StringToFind, args.StartSearchFrom, e.Direction);
// Tell the world that a search has occurred
var args2 = new AfterSearchingEventArgs(args.StringToFind, i);
OnAfterSearching(args2);
// If we found a match, tell the event
if (i != -1)
{
e.Index = i;
}
}